Adjustable lamp-standard



(No Model.)

0. LUETKE. ADJUSTABLE LAMP STANDARD.

No. 439,411. Patented 00t.'28, 1890.

ATTORNEYS WITNESSES.-

UNITED STATES PATENT OFFICE.

OSCAR LUETKE, OF BROOKLYN, NEV YORK.

ADJ USTABLE LAM P-STAN DARD.

SPECIFICATION forming part of Letters Patent No. 439,411, dated October 28, 1890.

Serial No. 358,488. (No model.)

To aZZ whom it may concern:

Be it known that I, OSCAR LU ETKE, of Brooklyn, in the county of Kings and State of New York, a citizen of the United States, have invented certain new and useful Improvements in Adjustable Lamp-Standards, of which the following is a specification.

This invention relates to improvements in that class of lamp-stands in which the lampsupporting device can be adjusted higher or lower and in any desired position.

The object of my invention is to provide a lamp-stand which is simple in construction, strong, and durable, and easily adjusted for any desired position.

The invention consists in the construction and combination of parts and details, as will be fully described herein after, and finally pointed out in the claim.

In the accompanying drawings, Figure 1 is a vertical longitudinal sectional View of my improved lamp-stand, parts being broken out; and Fig. 2 is a horizontal sectional view of the same on the line 2 2, Fig. 1.

Similar letters of reference indicate corresponding parts.

In the external tube A of the lamp-stand a lining-tube A is fastened, said lining-tube being preferably made of brass. In the liningtube A the sliding tube 13 is arranged, to the upper end of which a head 0 is fastened, which is used as a handle to raise or lower the tube B. In the top of the head 0 the screw D is screwed, to which is fastened a plate E for supporting a lamp E. A rod F, provided at its lower end with a tapering or wedge'shaped part G, has its upper end inserted in the bottom of the screw D, said up per end of the rod F being provided with a groove f, into which a pin f passes, that is held in the screw D, so that when the screw D is turned it can turn on the upper end of the rod F without turning said rod with it. From the lowerend of the tube B two rods K project downward and are provided at their lower ends with heads K, supporting a transverse plate L. A short distance above the transverse plate L a sliding plate P is arranged on the rods K, and between the plates L and P a spring M is interposed, which presses the plate P upward. Between he lower end of the tube B and the plate P the two wedge-shaped slides H are arranged, that are provided on their outer edges, that come in contact with the lining-tube A, with coverings II of leather or of cloth. The inner edges of said wedge-shaped slides H rest against the wedge-shaped lower end G of the rod F.

The operation is as follows: The handle 0 is seized and the tube B moved upward. The spring M is slightly compressed and the wedge-shaped slides II moved downward and toward each other, so that the outer edges are loose on the inner surface of the lining-tube A, thus permitting the tube B to be moved upward quite freely. As soon as the tube B is released the weight of the same and the parts supported by it exert a downward pressure and the spring M exerts an upward pressure, whereby the wedge-shaped slides H are forced outward against the sides of the liningtube A, and the outer edges of said slides bind on the lining-tube, whereby the tube B is locked and held in place. When the lamp is moved downward, the friction between the inner surfaces of the lining tube and the outer edges and the wedgeshaped slides II must be 0verco1nethat is to say, a greater power must be exerted in forcing the tube 13 downward. The device can easily be so adjusted as to require more orless powerto force it downward and also can be adjusted according to the weight of the lamp. In case the lamp is a heavy one, the plate E, supporting the lamp, is rotated in such a manner as to move the screw D downward, whereby the rod F, connected with the same, is also moved downward and the wedge-shaped lower end G forced a greater distance down between the Wedge-shaped slides II, whereby the friction between the slides II and the inner sides of the lining-tube A is increased and a lamp of greater weight can thus be conveniently held. If a lamp of less weight is to be held, the plate E is rotated in such a manner as to move the screw D and rod F upward. Thereby the wedge-shaped lower end G0): the rod F is moved upward, thus permitting the wedgeshaped slides II to move toward each othera greater distance,whereby the friction between said slides II and the inner surface of the lining-tube A is decreased.

Having thus described my invention, I

the same, a head on the upper end of the slidin g rod into which head said screw is screwed, and a lamp-support from the bottom of which said screw projects, substantially as set forth. I 5

In testimony that I claim the foregoing as my invention I have signed my name in presence of two subscribing witnesses.

OSCAR LUETKE.

Witnesses:

W. REIMHERR, C. SCHROEDER. 

